Three types of granules were observed in the neutrophils of red seabream Pagrus major parasitized with Ceratothoa verrucosa. In May-Grunwald ・ Giemsa staining preparation, two types were identified as ordinary chromophobic granules (oβG； type 1 (oϐG-1； without core) and type 2 (oϐG-2； with eosinophilic core)) which were observed in the neutrophils from non-parasitized fish. Other type, which consist of chromophobic core and eosinophilic surrounding, was considered inducible chromophobic granules (iϐG) because this type was not found in non-parasitized fish. Peroxidase activity was detected in all types of granules, but positive site was different among the granule types: oϐG-1, whole granule； oϐG-2, surrounding； iϐG, core.